Short tone bursts are better than clicks for cervical vestibular-evoked myogenic potentials in clinical practice.

Our aim is to compare short tone burst (STB)--and clicks--stimuli to evoke vestibular-evoked myogenic potentials (VEMPs) in healthy controls. A cross-sectional study in which VEMPs were measured in two sets of 185 and 55 normal volunteers by an air-conducted 500 Hz STBs and clicks, respectively. The test-retest reliability between different sessions was assessed in two subsets of 35 individuals. Moreover, 53 individuals were examined with both stimuli within the same session. Intraclass correlation coefficients (ICC) were used to assess reliability for P1 and N1 latencies, corrected amplitude and asymmetry ratio (AR). The results included that STBs produced a reliable response between different sessions (N = 35; [ICC] = 0.61-0.94, all p < 0.0001). Although clicks produced a reliable response for P1 and N1 latencies and corrected amplitudes (ICC = 0.62-0.74, all p < 0.0001), the amplitude ratio showed a lower reliability [ICC = 0.32 (-0.10 to 0.59)]. The amplitude of VEMP was consistently larger with 500 Hz STBs than clicks for a given sound pressure level. Within the same session, STBs evoked a response in 52/53 subjects (98%) whereas clicks evoked VEMPs only in 44/53 individuals (83%). Conclusions revealed that a 500 Hz STBs elicited consistently larger amplitudes, better reliability across recording sessions and fewer missing responses compared with click-induced VEMPs.

Vestibular evoked myogenic potentials and health-related quality of life in patients with vestibular neuritis.

OBJECTIVE: To evaluate the usefulness of vestibular evoked myogenic potentials (VEMPs) in subjects with vestibular neuritis (VN) and to determine the impact of the disease in health-related quality of life (HRQoL). STUDY DESIGN: Case series. SETTING: Tertiary referral center. PATIENTS: Fifty patients with VN (episode of sudden onset of prolonged vertigo [>24 h] associated with peripheral vestibular hypofunction, imbalance in absence of hearing loss, or other neurologic symptoms). INTERVENTION: VEMPs were measured in 41 patients by using an air-conducted 500 Hz tone burst. HRQoL was evaluated in all cases by the Medical Outcomes Study 36-Item Short Form Health Survey (SF-36) and Dizziness Handicap Inventory Short Form (DHI-S) instruments, after the acute episode was resolved. MAIN OUTCOME MEASURE: Latencies P1 or N1 peaks, corrected amplitude or the absence of response, for VEMPs; scores obtained in SF-36 and DHI-S instruments. RESULTS: VEMPs showed abnormal results in 21 (51%) of 41 cases, with an increase in ipsilateral latencies for P1 and N1 peaks being the most common finding. Three patients (7%) had ipsilateral abnormal VEMP response with normal caloric response, indicating isolated involvement of inferior vestibular nerve. The total score obtained for the DHI-S was 14.76 +/- 11.07 (range, 0-34/40), suggesting a variable impact among patients with VN. For the SF-36, scores in men with VN were worse than their age-matched controls for all dimensions, except for mental health. However, women only showed lower scores for general health and social function. CONCLUSION: Abnormal VEMP responses demonstrate the involvement of the inferior vestibular nerve in half of the patients with VN. Moreover, VN has a moderate impact in HRQoL, and it is perceived more disabling by men than women.

Dynamic visual acuity during head-thrust test in canal planes in healthy subjects and patients with vestibular neuritis.

CONCLUSIONS: Dynamic visual acuity (DVA) during the head-thrust test (htDVA) is reliable in normal subjects, having a high specificity for the horizontal canal, so it may be useful to monitor vestibular rehabilitation in patients with vestibular neuritis (VN). OBJECTIVE: To obtain reference values for htDVA in healthy individuals and to investigate the potential application in subjects with unilateral VN. METHODS: A total of 73 healthy individuals and 50 patients with unilateral VN were included. The DVA test was performed by adjusting a sensor on the subject's head to measure head velocity. During head thrust, the optotype flashed if the head velocity reached 150°/s, as previously defined, and a DVA score was obtained for each canal. RESULTS: The htDVA was reliable in normal subjects (intra-class correlation coefficient (ICC) = 0.44-0.71; p = 0.001-0.007). The htDVA score showed an age-dependent increase for all canals (p < 0.0001). The 95th percentile of htDVA was used as the criterion to consider htDVA as abnormal in patients with VN. In all, 44%, 30%, and 16% of patients had an increase in htDVA score for one, two or all three canals on the affected side. The sensitivity and specificity of the htDVA test for the horizontal canal were 22% and 85%, respectively.

Impact of bilaterality and headache on health-related quality of life in Meniere's disease.

OBJECTIVES: We analyzed the impact of bilaterality and headache on the health-related quality of life (HRQL) of patients with Meniere's disease (MD). METHODS: A case series including 86 patients with a diagnosis of definite MD according to the American Academy of Otolaryngology-Head and Neck Surgery (AAO-HNS) diagnostic criteria was evaluated by the Short Form 36 (SF-36) Health Instrument and the Dizziness Handicap Inventory Short Form (DHI-S). RESULTS: The scores on all scales of the SF-36 were significantly lower for bilateral MD than for unilateral cases, except for body pain. Both groups had scores worse than those of their sex- and age-matched normative population on all SF-36 scales (p = 0.017 to p = 0.0001), except for body pain in men. The DHI-S scores were also better for unilateral than for bilateral cases (p = 0.04), suggesting that the dizziness is perceived to be more disabling in bilateral MD. Migraine was significantly associated with bilateral MD (odds ratio, 3.58 [95% confidence interval, 1.25 to 10.31]; p = 0.021). Headache and score on the AAO-HNS functional scale, which evaluates the effect of vertigo attacks on daily activities, were two independent factors that explained a great part of the variability on all SF-36 scales, except for "role emotional" in bilateral MD. CONCLUSIONS: Patients with bilateral MD perceived their dizziness to be more disabling and had a worse HRQL than did patients with unilateral MD. Migraine was more frequently found in patients with bilateral involvement. Headache and score on the AAO-HNS functional scale were factors associated with the HRQL in bilateral MD.